I'm not using 256.44 due to various stability issues (see other thread(s)). I didn't provide an nvidia-bug-report because both systems are pretty different from each other, but still the issue is exactly the same.

Compute Visual Profiler is from CUDA 3.1 SDK, by the way, and I'm on x86_64 in both cases. Apart from that it's different GPUs and different Linux distributions.